The present invention concerns a procedure for detection and localization of objects on relatively flat ground and a device for application of the procedure.
In order to detect objects such as vehicles or buildings on relatively flat ground one possible approach is photographic comparison: photographs of known ground, in the absence of these objects, obtained by satellite or aerial photography for example, are compared with images obtained later in order to detect the arrival of the objects. Another method is simply to try to detect the objects on any photograph available.
The first approach requires prior reconnaissance of the ground in question and very precise guidance of the observation aircraft (by means of inertial guidance systems, for example). Not only is preliminary aerial observation sometimes impossible, but the survey must be made not too long in advance of the final photographic survey. Furthermore, the problems of localization necessitate complex and costly means, such as gyroscopes.
The second approach involves analysing an image of the ground in real time using shape recognition algorithms in order to locate certain types of objects. This procedure is complex and requires powerful data processing means.
Moreover, these procedures do not enable the distance from the aircraft to a target object to be measured nor the time of arrival of the object to be calculated, a disadvantage in the case where the guidance system is supposed to bring the aircraft directly over the object.